Re: How to obtain GNUstep environment values without openapp or GNUstep.sh?

[Richard Frith-Macdonald]

On 5 Dec 2006, at 02:07, Quentin Mathé wrote:

> Le 4 déc. 06 à 15:46, Nicola Pero a écrit :
>
> > What do you mean by 'enviromental' variables ?  Which variables  
> > exactly
> > do you need and why ? ;-)
>
> GNUSTEP_SYSTEM_ROOT, LD_LIBRARY_PATH etc.
> Just to be able to launch tool like gpbs with NSTask and without  
> modifying PATH or using opentool. I would like to do the same for  
> an application like Gorm (I mean without using openapp). If I know  
> GNUSTEP_SYSTEM_ROOT, I can find them easily because tools or  
> applications I plan to launch won't be moved once installed.  
> However GNUSTEP_SYSTEM_ROOT may change depending on the user or the  
> machine, so I either need a way to know its value or an API that  
> allows to search for tool and application path in standard  
> locations like GNUSTEP_SYSTEM_ROOT and GNUSTEP_LOCAL_ROOT.
>
> My daemonizer process is launched with a copy of libgnustep-base  
> put in /usr/lib because if I try to launch it without such copy, it  
> complains about libgnustep-base not available (not surprisingly  
> since it is installed by default in /System/Library/Libraries on my  
> machine).
> So I was supposing that environment variables I just mention  
> weren't set for this process, but perhaps I make a wrong assumption?
>
> > To locate the application binaries, you should use gnustep-base's  
> > NSBundle
> > methods to locate stuff in the various domains.
>
> Which methods? I don't understand how I can find an application  
> binary like Gorm with NSBundle (from another process). May be with  
> NSWorkspace though by running make_services first?
> But this wouldn't solve the problem for a tool like gpbs. I don't  
> think make_services cache information about installed tools.
>
> > One you have found the application binary, you just execute it.   
> > Give to
> > the application binary the same environment that your process is  
> > using,
> > and it will work. :-)
>
> If the environment is properly set, it should work :-)

1.  When you install GNUstep, you should add the paths of the  
directories containing GNUstep libraries to /etc/ld.so.conf and run  
the ldconfig program to update the systems cache of library paths.    
Putting libgnustep-base in /usr/lib has a similar effect, but you  
need to remember to do that for every library you might want to  
use ... so adding directories to /etc/ld.so.conf is less error prone  
as it means you are less likely to miss a library.

2. Use the NSSearchPathForDirectoriesInDomains() function to get a  
list (NSArray) of the directories that your tool may be in.

3. For each path in the list, call [NSString- 
stringByAppendingPathComponent:] to add the program name to the  
directory, call [NSFileManager-fileExistsAtPath:isDirectory:] to see  
if the named program exists and if it is a directory.

4a. If the path you found is a directory (an app) ... use the  
NSBundle API to access the directory bundle and determine the path to  
the executable in the bundle, then pass that to NSTask to launch.

4b. If the path is not a directory, just use it as the launch path  
for NSTask directly.